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SWINE PRACTICE 



America, and at this time it is the most important disease econom- 

 ically in the United States. 



Etiology. — The cause of hog cholera is attributed to a tiltrable 

 virus. The relation of a tiltrable virus to hog cholera was first 

 recognized by De Sehweinitz and Dorset in 1904, and similar investi- 

 gations by Boxymeyer of Michigan were also concluded in 1904. Other 

 investigators have verified the findings of De Sehweinitz and Dorset. 

 The virus of hog cholera occurs in the blood and therefore in prac- 



Fig. 



Acute hog cholera (Advanced Stage). 



tically all the tissues of the body of an infected swine. One to two 

 cubic centimeters of filtered blood serum from swine affected with 

 hog cholera will produce typical symptoms of this disease when 

 injected subcutaneously, intramuscularly, intraperitoneally, or 

 intravenously into a healthy, susceptible pig. The symptoms become 

 evident in from five to seven days after the inoculation. 



Eecently it has been reported by some investigators that the filtrable 

 virus of hog cholera has, been successfully cultivated artifically and 

 it has been further indicated that the cultivation of it may become 



